Integrated Reservoir Characterization, Modeling and Simulation of Lower Sihapas in Kurau Field, Sumatra, Indonesia

Abstract

A 1000 bopd was achieved from successful integrated study of Kurau Field in 2007 year. All best practices of the study describe in this paper. The objective of this study is to build a complete reservoir model from an integrated study involving all aspects of engineering & G&G, such as data review, G&G modeling, reservoir characterization, reservoir modeling and prediction, in order to optimize the development of Kurau Field. The milestone starts from interpreting the 3D seismic data, structural or zonation model, petrophysics analysis, reservoir characterization, static modeling, dynamic modeling, and proceeds until it reaches the development and performance prediction of Kurau Field. More than just a simple model, Kurau reservoir model resulted from all data and results from G&G such as interpretation of 3D seismic, G&G modeling (static model), environmental correction for well logs from Petrophysical Software analysis together with reservoir engineering works such as rock and fluid properties analysis, rock characterization and also production engineering aspects. Geomodeling software was used to build 3D seismic to reservoir modeling, with additional Simulation Software to complete the simulation. The history matching analysis shows a satisfactory level of production profile comparison results of model performances with actual production data. Several infill wells and even EOR potential can be identified from this reservoir simulation model. Using an integrated study workflow from G&G, Petrophysic and Reservoir Engineering work had greatly improved the reliability of this reservoir model. Recently updated, those infill wells proved able to yield an additional 1000 bopd to Kurau field, as previously predicted. An integrated study from Engineering & G&G Department was required when we attempted to build a reservoir model. Such a model can be used to determine infill well potential, work over result estimation and also the EOR project. Achieving an increment of the oil recovery factor is the most beneficial result from this reservoir simulation. Introduction Nowadays, reservoir simulations play an important role in the petroleum industry. Geological modeling, reservoir characterization, well performance analysis, infill well proposal and even EOR methods simulation can be applied. While it would seem to be more complicated than conventional techniques, reservoir simulation can on the other hand achieve or at least a yield preliminary pictures of the entire reservoir. With so many software releases available at present, the user just picks whichever is most suitable, depending on needs, compatibility with currently used software and also, of course, on the budget. The important rule to be borne in mind is that "garbage in, garbage out". Kurau Field in the EMP-Malacca Strait has been generated into a reservoir simulation. Within a 9 months' integrated study, a team can achieve a reliable reservoir simulation. Beginning with a 3D seismic interpretation and then combining this with a geological interpretation and reservoir characterization, the team can also generate a reasonable history matching. Geomodeling Software and Simulation Software were exploited to generate and run the model. Kurau Field itself has never been modeled before. The structure was quite complicated. Even it was only from the Lower Sihapas Formation, reservoir characterization plays an important role when a model is built. The new geophysics interpretation to define faults was carried out. Further, sand correlation was involved, along with reinterpretation due to new data from previous infill wells.

Best Practices in Static Modelling of a Coalbed Methane Field: An Example from the Bowen Basin in Australia

“…GIS data can be used for geological mapping, regional geological model building (Septiawan et al 2009), outcrop boundary determination, and analyses of fault features and distribution. At the east and west flanks of the syncline in our study area, there are a lot of erosional occurrences near the surface.…”